Pitman mechanism for power presses



May 25,1926. 1,586,171

E. W. ZEH

PITMAN MECHANISM FOR POWER PRESSES Fil August 26, 192 1 2 Sheets-Sheet 1 (8 I INVENTOR.

I W ATTORNEYS.

1 May 25, 1926. 1,586,171

. E. W. ZEH

PITMAN MECHANISM FOR POWER PRESSES Filed August 26. 1924 Sheets-Sheet 2 I I INVENTOR.

M ATTORNEYS.

Patented M 25, 192

UNITED STATES 1,586,171 PATENT OFFICE.

EDMUND W. ZEH, OF NEWABK, INEW JERSEY.

PITMAN MECHANISM FOR POWER PRESSES.

Application filed August 26, 1924. Serial No. 734,186.

screw in a direction diametric of said screw;

to provide an engagement of said clamping block with the main eccentric portion which shall ensure a strong and firm engagement of the adjustable parts of the pitman; to secure an improved and simplified means of adjusting the connecting screws ofthe pitmen simultaneously, and toobtain other advantages and results as may be brought out p by the following description.

Referring to the accompanying drawings, in which the same numerals of reference designate corresponding and like parts throughout the several views.

Figure 1 is a front elevation of a power press embodying my improvements, certain of the parts being in central vertical section to better illustrate the invention;

Figure 2 is a horizontal cross-section on line 2-2 of Fig. 1, looking downward;

Figure 3 is an edge view of the right hand pitman in Fig. 1, illustrating the clamping block construction; w i

Figure 4 is a similar view illustrating a modified form of clamping block construction, and i Figure 5 isan inner face view of such a modified clamping block.

In said drawings I have shown my improvements embodied in a power press of '-commorr and" well known type, having a frame with side pieces or housings 1,1. a bed 2 and a top-leaf 3; journaled in said side pieces and top-leaf is a shaft 4 having eccentric portions 5, 5, which are connected by pitmen 6, 6, to a hammer 7, adapted to reciprocate toward and away from the bed 2 between the side pieces 1, -1. The shaft 4 is shown having a driving pulley 8 upon one end .of itself, outside the frame of the press, and any usual clutch-means 81 isprovided to cause the press to operate as desired even though the driving pulley rotates continuclamping ously. This press is shown only for purposes of illustration, it being understood that my improvements to be described asapplied to it can be applied to presses of various other constructions and I do not wish to be understood as limiting myself in that respect.

The hammer 7 is guided in its up and down movements by guideways on the sidepi'eces 1, 1, consisting briefly of a fixed gib 9 at one side of a projection 10 on the hammer and an adjustable gib 9 at the other side of said projection. These features form the subject-matter of my copending application Serial No. 734,185, filed August 26, 1924, and therefore they will not be further described here; any other guide means could be used, as far as the present invention is concerned.

Each of the pitmen 6 must be provided with means for longitudinal adjustment in'.

order to adjust the hammer 7 toward and away from the bed 2, and I have shown this done by a head 11 which is connected to the body 12 of the pitman by a screw 13, said screw being swivelly connected to the head, as at 14, and threaded into the body portion 12. Means hereinafter described are pro-K vided for turning these screws, and for them when adjusted I cut outs. lateral block 15 at the end of each pitman body portion, on a planeintersecting the screw 13, and mount said block upon screws 16, 16 extending loosely through it and threaded into the body portion on opposite sides of the screw 1350 that by turning uponsaid screws the block can be clamped against 1 the screw. It will be noted that the direction of this clamping is diametric of the screw 13, so that there is minimum tendency to displace the threads of the block with respect to the threads of the screw and cause unnecessarywear between themby the heavy strain of operating the press. out such a block on a'plane longitudinally through the middle of the screw would entirely release that portion of the screw from holding engagement with'the body portion and weaken the pitman, I do not cut in so far as that, but only far' enough to expose suflicient surface of the screw for clamping purposes, say half way to the center of the screw or'less, as indicated in Figures 2 and 3 most clearly. face of the screw for clamping purposes and Since to out This exposes suflicient sur- I still leaves that part of the screw held or encircled enough to prevent its escape and avoid weakening the pitman. I thus secure a firm clamping of the pitman screw without serious impairment of the pitman.

In order to better support the clamping block and give it an engagement with the body portion 12 of the pitman, so as to relieve the screws 16 of strain longitudinally of the pitman, I prefer to provide a step 17 upon the surface 18 of the body of the pitman against which the clamping block 15* seats, see Figures 4 and 5, said clamping block being recessed as at 19 to receive said step and rest upon it. This supports the clamping block against strain longitudinally 'of the pitman and relieves the screws 16, 16, so that the construction is made stronger and firmer without materially lessening the clamping effect.

In order to adjust the two pitman screws simultaneously and equally, I mount upon each of them a bevel gear 20 which is rotatably fast to the screw and is positioned between the head 11 and body portion 12 of the pitman, with the gear teeth facing downwardly. I'then form in the upper edges of the two heads 11, 11, at their adjacent sides, radial grooves 21, 21 which. form bearings for a short shaft 22 and hold the same substantially in a plane through the'axial lines of the two adjusting screws 11. Upon the ends of this shaft 22 are mounted pinions 23, 23 meshingone with each of the said bevel gears 20, 20, so that by turning the said shaft 22 the said bevel gears 20, 20 and therefore the adjusting screws 13, 13 can. be turned simultaneously, it being understood that the screws are for this purpose threaded oppositely, that is, one right hand and the other left hand. I have shown the shaft 22 as squared for its intermediate exposed POI"? tion and round at its ends which lie in the bearings 21, 21, said pinions being pinned or otherwise made fast to the round parts of the shaft. By this means a wrench can be applied to the middle portion of the shaft for turning it, although it will be understood that other equivalent detail constructions could be employed. By. the construction thus described, I secure great simplicity and effectiveness, and provide a construction which is easily manufactured and operated with no likelihood ofbecoming damaged or getting out of order. 1

Various modifications and changes-may be made in manufacturing my improvements, by those skilled in the art, without departing from the spirit and scope of the invention,

and I do not wish to be understood as restricting myself except as required by the upon opposite sides of said screw for clamp-' ing saidblock against the screw in a direction diametric of said screw.

2. In a press, thecombination with a plurality ofpitmen each having a body portion a head and a screw swivelly connected to said head and threaded longitudinally into said body portion, said heads providing at their adjacent sides alined bearings, of a shaft in said bearings, pinions on the ends of said shaft, and bevel gears one on each screw above the adjacentpinion and having teeth at its under side engaging said pinion.

3. In a press, the combination with a plurality of pitmen each-having a body portion a head and a screw swivelly connected to said head and threaded longitudinally into said body portion, said heads having at their adjacent sides alined radial grooves in their ends, of a shaft journaled at its ends in said grooves, pinions fixed upon the ends of said shaft next said grooves, and bevel gears on the screws engaging said pinions 4. In a press, the combination with a p lurality of pitmen each having a body portlon a head and a screw swivelly connected to sa d head and threaded longitudinally into sa d body portion, said heads providing at their adjacent sides, alined bearings,'of a shaft having ends journaled in said bearings and intermediate means for turning, pmlons on said shaft adjacent said journaled ends and held against movement away therefrom, and bevel gears one on each screw above the adjacent pinion and engaging the same.

5. In a press, the combination with a plurality of pitmen each having a body portion a head and a screw swivelly connected to sald head and threaded longitudinally into said body portion, said hea rovidin at their adjacent sides alined bearings, o a shaft having a squared middle portion and reduced round ends journaled in said bearings, pinions fast on s'aidrounded endsad acent thesquared portion, and bevel gears one on each'screw above the ad acent P1111011 and engaging. the same.

EDMUND w. ZEH. 

